This is an ignition exciter for the J-2 liquid fuel rocket engine. An ignition exciter is a device that generates a high-energy pulse to an igniter (similar to an automobile coil). The exciter shown here is from early J-2 hardware and dates to 1961. The J-2 engine system was the first to use this type ignition system at Rocketdyne. An engine restart was required on the J-2 while in Earth orbit mode to send the Apollo spacecraft on its way to the Moon. On previous engine systems, pyrotechnic igniters were used as one one-start igniters were required.
The J-2 engine, using liquid hydrogen and liquid oxygen, was the powerplant for the second and third stages of the Saturn V launch vehicle which took astronauts to the Moon in the Apollo program. The Saturn V's second stage had a cluster of five J-2s, while the third stage had a single J-2. This exciter was recovered from Rocketdyne's VTS-1 (Vertical Test Stand-1) area, before the stand was torn down in 1996.
The Rocketdyne Division of Rockwell International donated this artifact to the Museum in 2001.
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.